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S M Long

Publications and source records attributed to S M Long.

25 records · Page 2Linked to original sources
PubMed2001

A technique for the treatment of sternal infections using the Vacuum Assisted Closure device.

BACKGROUND: Sternal infections after median sternotomy remain a serious cause of postoperative morbidity and mortality. The treatment of sternal infections has evolved over the past few decades, and now aggressive surgical debridement with rotational muscle flap closure has provided an acceptable means of managing this complication. However, there are several disadvantages with this approach, mainly related to the morbidity associated with serial debridements with dressing changes and open packing until the wound is closed. Other disadvantages include potential morbidity and mortality associated with the shearing forces between the beating heart and the debrided sternal edges, and the need to paralyze the patient during the period after debridement. METHODS: Our method of managing sternal infections is based on the triad of prompt surgical debridement, serial quantitative wound cultures, and the use of the Vacuum Assisted Closure (VAC) device (KCI International, San Antonio, TX). Following debridement and irrigation, a biopsy of the healthy appearing bone is sent for quantitative culture. If culture results are favorable, the wound is then fitted with the VAC device, which consists of a non-collapsible, open-cell, polyurethane sponge with embedded vacuum tubing, a vacuum pump, and transparent adhesive dressing. When systemic signs of infection and quantitative cultures indicate the resolution of the local infection, regional muscle flap or primary wound closure is performed. CONCLUSIONS: The VAC serves as a bridge to sternal wound closure and is a safe and effective therapeutic strategy for patients with impaired physiologic reserve and/or highly contaminated wounds. We feel that it is also reasonable to consider the VAC as a preventive strategy against right ventricular rupture. Furthermore, because the firmness of the vacuum sponge apparatus acts as an impressive sternal stabilizer, post-debridement extubation is possible, reducing the need for prolonged paralysis and mechanical ventilation. This stabilization also allows early postoperative ambulation with the VAC in place. In summary, we believe that the VAC device offers an effective means of managing patients with sternal infections.

Debridement↗
PubMed2000

Epidermal growth factor augments postpneumonectomy lung growth.

OBJECTIVE: Epidermal growth factor has been shown to play an important role in prenatal and postnatal lung development, but little is known about its effects on adult lung growth. We hypothesized that postpneumonectomy compensatory lung growth can be augmented by the administration of epidermal growth factor. METHODS: Adult Sprague-Dawley rats were divided into 3 groups. Sham left thoracotomy was performed in the first group (group C), left pneumonectomy in the second group (group P), and left pneumonectomy with administration of epidermal growth factor (0.2 microgram/g body weight intraperitoneally, at 72-hour intervals) in the third group (group E). The right lung growth was studied in each group 1, 3, 5, 10, and 21 days after the operation. Lung weights (in grams) and volumes (in milliliters) were expressed as a ratio to the total body weight (in kilograms) (lung weight and volume indices). Epidermal growth factor receptor was quantitated by using Western blotting. RESULTS: Using analysis of variance and contrast analysis, we noted a significant increase in lung weight index in group E versus group P rats at 3 days (3.08 vs 2.75; P =.034) and 21 days (4.62 vs 3.61; P =.006). Lung volume index was significantly increased in group E versus group P rats at 5 (16.98 vs 15.09), 10 (24.48 vs 18.81), and 21 (28.54 vs 21.01) days (P <.001). Epidermal growth factor receptor was noted to be up-regulated in the lungs of animals that received exogenous epidermal growth factor. CONCLUSIONS: This study demonstrates that administration of exogenous epidermal growth factor has a significant effect on postpneumonectomy lung growth. This process may be mediated by an up-regulation of growth factor receptor expression in the contralateral lung.

Analysis of Variance↗
PubMed1994

Polyarteritis nodosa presenting as acute blindness.

Polyarteritis nodosa is a vasculitic disease commonly involving coronary arteries, mesenteric arteries, kidneys, muscles, and vasa nervorum. Central nervous system involvement in polyarteritis nodosa is unusual and tends to occur later in the course of disease. We report the case of a 23-year-old woman who presented to our emergency department with acute loss of vision. Her evaluation led to a diagnosis of polyarteritis nodosa. We present what may be the first published case report of polyarteritis nodosa presenting as acute bilateral visual loss.

Acute Disease↗
PubMedDate not supplied

Role of thyroid hormones in hepatic effects of peroxisome proliferators.

Peroxisome proliferators are endocrine disrupting chemicals that cause liver tumors in rodents but not humans. Although the receptor that mediates key hepatic effects, the peroxisome proliferator-activated receptor alpha (PPAR-alpha), and its endogenous ligands have been identified, the mechanism whereby these commonly used chemicals cause liver tumors in rodents has yet to be elucidated. Species differences in PPAR-alpha and DNA response elements may explain some of the variability in response upon exposure to peroxisome proliferators. The possibility that thyroid-modulating effects of peroxisome proliferators may contribute to the hepatic effects of peroxisome proliferators has yet to be fully explored. When the potent peroxisome proliferator, WY-14,643, was given to hypothyroid rats, there was a blunting of the hepatomegaly and hepatocyte proliferative responses seen in thyroid-intact animals. Acyl-CoA oxidase activity was unaltered by changes in thyroid hormone status. In addition, preliminary evidence indicates that peroxisome proliferators increased hepatic thyroid receptor (TRalpha1) expression, but TRalpha1 levels in liver tumors were similar to those in unexposed animals. Significant differences between humans and rodents with respect to thyroid hormone physiology and metabolism, in conjunction with the results of these studies, may be indicative of yet another mechanism to explain differential sensitivity to hepatic effects of peroxisome proliferators.

Animals↗
PubMedDate not supplied

Carotid arteriography impacts carotid stenosis management.

Recent literature advocates carotid endarterectomy on duplex alone. The authors hypothesized that carotid angiography adds information that alters clinical management in a substantial number of patients compared to the use of carotid duplex examination alone. The records of 182 consecutive patients who underwent carotid artery duplex and subsequent carotid/cerebral angiography for suspected carotid artery stenosis between January 1998 and April 1999 were reviewed retrospectively. Carotid artery duplex examinations were stratified based on stenosis: < or =39%, 40% to 59%, 60% to 79% (moderate), 80% to 99% (severe), 100%. Carotid stenosis on angiograms was determined by NASCET criteria. New information found at angiography included vertebral, subclavian, or arch atherosclerosis, intracranial pathosis, or a change in duplex stenosis category to a degree of stenosis not requiring surgery. Clinical importance was attributed to angiograms that altered the patients' management plan. Angiography provided additional information in 53% (97/182) of patients. Vertebral disease was found in 25.1%, subclavian disease in 16.4%, intracranial disease in 15.3%, aortic arch disease in 3.3%. Patient treatment was altered in 30% (55/182). Angiographic findings downgraded the stenosis to medical therapy in 20.9% (38/182). The surgical plan was influenced in 5.5% (10/182). Nine intracranial aneurysms were discovered. Carotid angiography was essential for vascular bypass surgery planning in 3.3% (6/182). Angioplasty was performed in 2.2% (4/182). The accurate determination of stenosis is critical in determining optimal treatment of patients with carotid artery stenosis. Routine carotid angiography remains valuable in the clinical treatment of these patients.

Aged↗